Fancy completion all over Emacs, not just for buffers and files. https://github.com/DarwinAwardWinner/ido-completing-read-plus

Ryan C. Thompson fccee51bdf Major restructuring, untested 12 lat temu
ChangeLog 9cab43bbdf Restore compatibility with Emacs 23 and earlier 12 lat temu
README.md 7a258468d4 Version 1.7 12 lat temu
ido-ubiquitous.el fccee51bdf Major restructuring, untested 11 lat temu

README.md

ido-ubiquitous

Gimme some ido... everywhere!

Does what you were really hoping for when you did (setq ido-everywhere t). Replaces stock emacs completion with ido completion wherever it is possible to do so without breaking things.

Get it from http://marmalade-repo.org/packages/ido-ubiquitous